Electronics Forum | Tue Nov 09 12:00:41 EST 2004 | Dreamsniper
Problem: PQFP208 Pad Width specified as 11.8 thou, PCB came and they are 9.5 thou. Component Lead Width is 10 thou to 10.6 thou. Operators have difficulty aligning and inspecting. Issue: Fed back to PCB Fab House and they said IPC accepts +/- 20% fo
Electronics Forum | Tue Nov 09 16:24:53 EST 2004 | davef
Your board fabricator is: * Correct that +-20% is the tolerance of the IPC specification * A moroon for not correcting the artwork to compensate for etch factors Find a new supplier. Baring that, if the SMT pad width is critical, you can specify th
Electronics Forum | Tue Nov 16 11:11:18 EST 2004 | iva
Hello Charlie, For Application of thermal conductive glue by dispensing, Luxeon recommends Amicon E3503 from Emerson and Cuming (www.emersoncuming.com) for its standard Luxeon Power Light Sources. For optimal thermal connection it is important that
Electronics Forum | Wed Nov 10 15:18:15 EST 2004 | Dave G
Let's go for Ugly..... I've used these in the past for attaching connectors to boards and tabbed Transistors to extruded Aluminum heatsinks with mixed results. The concept is great but, in practice there are some headaches to deal with. We've gotten
Electronics Forum | Tue Nov 09 22:43:39 EST 2004 | Fengang
Hi all, Yesterday I met a VCO(Vector-Controlled Oscillator) supplier, who provided the component spec -- peak temperature over 240 centigrade stands 7secs. But this spec is obviously different from our spec -- 260 centigrade 10secs. They told me th
Electronics Forum | Fri Nov 12 10:47:03 EST 2004 | davef
Fengang: You say, "And I have investigated a lot of component manufacturers, it seems like that most of them just change the plating of components' lead for lead free. That means lead free process has little impact on the component manufacturers, is
Electronics Forum | Thu Nov 11 08:06:00 EST 2004 | no gel pig fan
I would definately try to sell the bosses on the Grid-lok over the gel piggies. We evaluated both and wound up buying the Gel (for close to the same money). On an MPM if you put enough gel packs in the vacuum box (to support the board) it holds the b
Electronics Forum | Thu Nov 11 11:11:18 EST 2004 | clampron
D.B., You are justified in your concern over the last requirement. I have been imposed by a customer with the same hand solder/rework requirements. It seems the biggest concern is thermally shocking ceramic chips. You are much less likely to do this
Electronics Forum | Thu Nov 11 17:49:11 EST 2004 | pdeuel
We are having a problem with our AP-24x printer. When the vacuum motor spins up we get a 60 hz buzz into the DC drivers for the forcers and the stencle wiper. We also indicate a main power drop from 115 vac to 80 vac. The vacuum motor checks out good
Electronics Forum | Thu Nov 11 18:36:29 EST 2004 | valuems
Hello We have been working on the MPM's for over 11 years now. And we have never had any trouble with that circuit, just goes to show you. If you have one of the old, old manuals you will find a lot of errors. They corrected them as they went. We
